Apparatus for the withdrawal of sheets or the like



June 2, 1931. l A. WINKLER ET AL 1,808,586

APPARATUS FOR THE'WITHDRAWAL 0F SHEETS OR THE LIKE Filed Aug. 31, 19291zz 18 4 lhrenicms,

Al red Win/etercmol Marx Dfin/vebier: v W 755019194 Patented June '2,1931 UNITED STATES PATENT OFFICE 'I Annual) winxtnn Annmax nimnniamn, ornnuwrnn, cnnmny APPARATUS non 'rnn WITHDRAWAL or. 'snnnrs on 'IHE LIKEApplication filed August 31, 1929, Serial No.

. 6 groups orbundlesof sheets or leaves folded together, and theinvention-relates more particularly to apparatus in which the withdrawalis efi'ectedby pulling the sheet from beneath the stack in a directiondiagonal to 10 the sheet or approximately in that direction,

and in whichthe sheet withdrawn from the stack, is moved in a directionwhich is approximately opposite to the direction of its withdrawal fromthe stack.- ,Such arrangements are employed mainly in the handling ofsheets that have been folded once or several times and have to bewithdrawn individually from a stack from below, as is the case,for'example, in, newspaper inserting or assembling machines. For the.purpose of lessening the pressure resting upon the low-.

est sheet in the stack an inclined position of the stack has proved tobe the most favorable or even the only practicalone. In this coninection it is necessary to place the sheets-in the inclined stack insuch mannerthat they have their longitudinal and transverse foldsresting against the stack stops, so that the corner formed by these twofolds is situated lowest. The vrestingof the folds against/the stackstops produces afar more uniform position of the sheets in the stackthan if the open and frequently irregular edges were to rest againstsuch stops. Furthermore, since in' the case of doubly folded sheets, forex- -ample in the case of newspapers, the separation of one sheet fromthe stack is most advantag'eous'ly commenced at the corner formed by thetwo folds or else, in case of sheets. folded once, at the corner formedby one foldand one open edge, because a separation can be more easilyand positively ef fected at this point. It is therefore necessary togrip the lowermost sheet by the corner that is situated lowest and whichis at the same time also the lowest corner-of the.

stack, in .order first to separate-this corner from the .one situatedabove it and then to brought, by the suction device itself, between Theoptional handling of single and .of

pull the sheet from beneath the stack,

389,730, and in Germany September 1, 192 8.

folded sheets in one and the same apparatus requires, in addition, aparticular guidance of the sheet afterit has been withdrawn from thestack. Folded sheets must under no circumstances undergo a simultaneousbending in different directions, as displacements within the sheetlayers thus occur, which during the passage between pairs of guiderollers may easily result in wrinkling. and the production of folds.Structural difliculties, however, prevent the further conveyance of thesheet withdrawn from beneath the stack in the same direction ofmotionasthat of this withdrawal. The :sheet must therefore be guided into a newdirection in such manner that it is conducted between .draw-in rollerswhich, bending-it only once, impart to it a new direction of motion,which is in most cases approximately opposite to that of the withdrawalfrom beneath the 7 stack, liut extends" in a horizontal plane. In thismanner the sheet is conveyed back under thestack." p

For the handling of single sheets without folds similar apparatus havebecome known. For example, German Patent 27 6,374 shows means for thewithdrawalof'the lowest sheet from a stack. In that connection we areconcerned with the drawing-in of sheets or blanks for the manufacture.of'envelopes into 8 a folding machine, i. e., with sheets or blanks ofrelatively great flexibility, which furthermore admit of the employmentof a perpendicular stack because in that case the weight which restsupon the lowest sheet that is to be 8 withdrawn is not too .great'andbecause there is no question of an imprinting of the sheets withconsequent increase in the friction. In this apparatus use is made'oftwo discs with .a V-shaped excision, which discs rotate con- 9 trary toone another and upon which the stack rests at-itsfront edge.' At everyrotation of the discs this front edge'of the sheet which is lowest isdrawn through the excisions of the disc by means of a suction device, sothat the discs in their further rotation come to be above this sheet.-At the same time the'sheet corner which has thus been. bent away' is apair of draw-in rollers which receive it and thereby withdraw the sheetfrom beneath the stack in order to conduct it to further guides andconveyor means in which it assumes a direction of motion which isopposite to that which it has at its withdrawal from the stack.

.large diameter, and neither a suction device nor a needle apparatusoperates with sufficient positivencss to bend the large corner surfaceof each sheet away so far that it gets between the large upper rollerand its cooperating under. roller and is positively seized between thetwo.

On the other hand, the apparatus according to the present inventionadmits of the handling of sheets of the two types mentioned, i. e., ofsingle sheets that have not been folded and of single or multiple sheetsthat have been folded once or several times. Itdepends upon theemployment of two bellshaped devices which rotate contrary to oneanother and which are generally of truncated cone shape and are arrangeddirectly beneath the stack symmetrically on both sides of an imaginaryline drawn through the lower corner of the stack in the direction ofwithdrawal of the shcet,'in such a manner that the lowest sheet of thestack rests upon said devices with its fold edges that form the lowercorner. In their upper faces and in their peripheral surfaces thebell-shaped devices have excisions of such a kind that'at their rotationbelow the lowest sheet, which has been bulged out or lifted off only toa small extent ,within the plane of its lowest edgeby means of a needleapparatus or a suction device, they penetrate into the stacksimultaneously from both sides and at their further rotation convey thisfront edge of the lowest sheet between their conical peripheral surfaceand an upper roller which cooperates with an under roller. In thisbending-down process the foremost point of the bent-down sheet cornerenters an excision of the under roller, so that it is seized between theupper roller and the under roller, and the sheet is thereby drawn outfrom beneatl the stack.

The novel action of the apparatus in accordance with the presentinvention, in comparison with other known arrangements consists notmerely in the fact that the bending-down of the sheet edge between thedraw-in rollers by the bells takes place with absolute positiveness evenin the case of very stiff sheets, but, on the contrary, it is alsoparticularly important that the bells assure the bending-down of thesheet with a bendingedge which remains absolutely constant in In orderto assure the perfect application of the bent-down sheet corner againstthe upper draw-in-r'oller, there is further provided between the twobells an application device which applies the outermost point of thesheet edge completely against the upper draw-in roller and holds it fastuntil it is seized by the under roller.

One form of the improved apparatus is illustrated in the drawingswhereon:

Fig. 1 is a vertical longitudinal section of the apparatus taken on theline I-I of Fig. 2;

Fig. 2 is a view looking in the direction of the arrow II of Fig. 1;

Fig. 3 is a side view of one of the bells looking in the direction ofthe arrow III of Fig. 2.

' Upon an inclined stack plate 1 a sheet stack 2, is supported and it isassumed in the example shown in the drawings that the apparatus ishandling doubly folded sheets, for example, newspapers, which have asimple transverse fold at 3 (Fig. 2) and a longitudinal fold 4 that liesdouble. The corner 5 that is formed by these two folds is accordinglysituated at the lowermost part of the stack 2. The position of thefolded sheets in the stack is assured by the stack stops 6 and 6' insuch manner that the transverse "folds 3 rest against the stop 6v andthe longi- Well-known per se diminishes the friction that occurs duringthe withdrawal of the lowermost sheet from the stack. On the other handthe engagement of the folded edges 3 and 4 against the stops 6 and 6assures a uniform positioning of the sheets in the stack.

' However, the corner 5. which is most favorable for the starting of theseparation of the lowest sheet from the stack and which is formed by thetransverse fold 3 and the longitudinal fold 4 is located at the lowestpoint so that the withdrawal of the lowest sheet from beneath the stackmust take place in the direction indicated by its inclined or obliqueposition, i. e., by its inclination to the horizontal. The necessarymeans for this withdrawal do not for structural reasons permit animmediate further conveyance of the stack.

that even thick sheets, for example, newspapers containing many pages,are not wrinkled, creased "or folded. These reasons have already led, inthe case of known apparatus, to the employment of a pair of draw-inrollers 7, 8 situated under the stack, of which pair the upper'roller 7has such a diameter that the thickest sheet that is passed around itreceives no damage due to the bending necessary in the process. With theincrease inthe diameter of the upper roller 7, however, there is also an.incre'ase in the superficial area of the edge of the lowest sheet whichmust be bent overto bringit between this upper roller 7 and itsco-operating under roller 8. The magnitude of the bending-over angle isalso increased, and with increased thickness of the sheets, the resistanee to bending also increases. Neither a suction device nor a needleapparatus nor any other hitherto known device assures per se a positivebending-over of the sheet corner and its introduction between thedraw-in rollers. In accordance with the present invention the followingapparatus is therefore provided for this purpose.

The. lowest corner 5 of the lowest sheet of the stack andthereby alsothat of the entire stack 2 rests with the edges 3 and 4, by which itisformed upon the upper surface of the bells 9 and 10, which bells 9'and10. are situated in front .of the upper draw-in roller 7, symmetricallyon both sides of air imaginary line extending through the lowest sheetcorner 5 and in the plane of the lowest sheet of the V The faces of thesaid bells are situated in the same plane as the stack plate 1. Thesebells 9, 10 are somewhat in the form of a truncated hollow cone, buttheir peripheral surfaces are curved so as to extend concentrically orapproximately concentrically with the peripheral surface of the roller7. In their faces and peripheral surfaces excisions 9 and 10"respectively are formed in such a way that there is formed by eachexcision in the face a tongue 11, which tongues,-

at the rotation of the bells in the direction of the arrows (Fig. 2'),penetrate laterally under the lowest sheet, as longas its positionremains unchanged, into its edges 3 and 4 in such a manner that theseedges represent a chord of the circular path of the tongues. Between thetwo bells 9 and 10 there-is providedv a suitable -devicein the exampleshown in the drawings,.a needle apparatus ment upwards, bulges it.downwardly away from the next sheet in such manner that it assumesapproximately the position shown in broken lines in Fig. 1 .of thedrawings, so

that bet-ween the lowermost sheet and the one the foremost corner 5 ofthe lowestworkinclined thereto. 12-7-which seizes the lowest'sheet ofthe stack in the vicinity of its edge 5 and, by displacejust aboveitthere is formed a recess 13into which the tongues 11 of the rotatingbells 9 and 10 penetrate simultaneously from both sides, and at a ratheracute angle, so that thispenetration is assured even if the recess 13 isvery narrow. On further rotation of the bells the sheets edges 3 and 4are seized by the edges 14 of the excisions 9' and 10' which extend inthe peripheral surfaces of the bells. In consequence thereof, since theneedle apparatus 12 has in the meantime moved back,

piece is bent down through the excisions 9' and 10' in the faces of thebells in such a way that it must necessarily lie between the peripheralsurfaces of the bells and the periph-' eral surface of the roller 7. Inthis process, as distinguished from other known methods, the bent downpart of the sheet is in no way damaged or displaced in the narrow spacebetween the bells and the roller 7; nor can the bending curve of thesheet edge change appreciably in the interval between the bells and theroller 7 Thisis of particular importance, because the foremost point .ofthe edge 5 must arrive with positiveness in a re-- c'ess 8' of thehollow under draw-in roller 7 and thereby be completely pulled outfrombeneath the stack. It is evident that a displacement of the bending edge'in the direction of the corner 5, i. e., too great av devia tion of thebending curve frond the surface of the roller 7, might cause theforemost corner of the sheet to fail to enter the recess 8" of thecylinder 8 so that the sheet would not be removed from the stack.

In order positively to assure the application of the bent-down sheetedge against the upper roller 7 and its entranceinto the excision 8' ofthe under roller 8 even in the case of very thick sheets, a'spec'falrotating application device is further provided between and below thebells 9 and 10. This device consists of round iron arms 15 which arescrewed into a hub piece 17 fastened on the shaft 16, and each have anarc-shaped bent-over portion 18 arranged eccentrically to the axis'ofrotation 16. On the rotation of the applica, tion device, in a clockwisedirection (Fig. 2), the portions 18 engage any bent sheet portion thatmay possibly be too .far distant from the upper roller 7, and apply itagainst the said roller so that it must positively enter the excision 8of the roller 8. According to the circumstances in any particular case,the shaft 17 of the application devices may be placed parallel to thoseof the bells 9 and 10'or else As being irrelevant for the actualinvention,-.the drives for the apparatus vcont'rivance are notillustrated in the drawings. The drive of the under roller-8 may beeffected. directly from the upper roller 7b way of spur gears, whileitis assumed in t e drawings that the bells 9 and 10 are driven 1n a"suitable manner'by bevel gears 21 and 22 situated on the shafts 19 and20, and that the application device is driven by means of a bevel gear23 fastened upon its shaft 16.

For the operation of the apparatus it is of no importance howmanyrevolutions or partial revolutions the upper roller 7 executes for thehandling of each sheet as long as no particular work on each sheet isassigned to it and no operating tools are driven from its shaft. inaccordance with the example shown in the drawings, it is furthermoreassumed that the under roller 8 executes two revolutions for thehandling of each sheet,

while the bells 9 and 10 are provided with two excisions 9 and 10 eachand therefore have to execute only half a revolution for the handling ofone sheet. The same thing is true also of the application device, whichcarries two arms 15, diametrically displaced with respect to each otherand whose portions 18 attend to the actual application.

From the pair of rollers 78 the workpiece is conducted between a beltpassed 25 around the roller 24, and the roller 7 and is conveyed.forward from this point in the manner that may be most suitable in eachparticular case. For the purpose of adaptation to the differentthicknesses of the sheets the rollers 8 and 24 are supported in levers;26 and .27 which are acted on by springs 28 and 29, so that they areboth constantly pressed against the roller 7. We claim: I

- 1. Apparatus whereby the lowermostsheet is withdrawn in a diagonaldirection from a stack of single or folded sheets or the like,comprising means for supporting the stack in an inclined position withone corner of the 40 stack at the foot of the incline, means for forminga recess between the lowermost sheet,

and the one next thereto, a tongue adapted to penetrate said recess tobenddown the lowermost sheet at the said corner of the stack, arelatively large main roller mounted beneath the stack, a relativelysmall counter- '"roller cooperating therewith and recessed centrally of.its length to receive the corner of the sheet, and a rotary bell-shapedmember carrying said tongue and mounted on an axis substantiallyvparallel to the perpendicular axis of the stack and having a curvedperipheral'surface adapted to lie close to and in concentric relation tothe peripheral surface of the main. roller to bring the sheet into closeand uniform contact with the main roller and to insert the corner of thesheet into the said recess in the counter-roller.

2. Apparatus whereby the lowermost sheet 9 is withdrawn in a diagonaldirection from a stack ofsingle or folded sheets or the like, comprisingmeans for forming a recess bee tween the lowermost sheet and the onenext thereto, tongues "adapted to penetrate the two 5' opposite sides ofsaid recess tobend down the lowermost sheet, a main roller mountedbeneath the stack, a recessed counter-roller cooperating therewith, anda pair of rotary bell-shaped members carrying said tongues and mountedon axes substantially parallel to the perpendicular axis of the stackand with curved peripheral surfaces shaped and arranged to bend the.sheets uniformly against the peripheral surface of the said main rollerwith the leading corner of the sheet projecting into the range of thecounterroller.

3. Apparatus whereby the lowermost sheet is withdrawn in a diagonaldirection from a stack of single or folded sheets or the like,comprising means for forming a recess between the lowermost sheet andthe one next thereto, tongues adapted to penetrate the two oppositesides of said recess to bend down the lowermost sheet, a main rollermounted beneath the stack, a counter-roller co-operating therewith andrecessed centrally of its length to receive the leading corner of thesheet, and a pair of rotary members shaped to form said tongues andperipheral surfaces curved and arranged to lie concentrically and closeto the periphery of the main roller to bend the sheet against saidroller and into the recess in the counter-rollerl 4. Apparatus wherebythe lowermost sheet is withdrawn in a diagonal direction from a stack-ofsingle or folded sheets or the like, comprising meansfor forming arecess between the lowermost sheet and the one next thereto, tonguesadapted to penetrate said recess to bend down the lowermost sheet, a

main roller mounted beneath the stack, a re cessed counter-rollerco-operating therewith, a pair of rotary bell-shaped members carryingsaid tongues and mounted on axes substantially parallel to theperpendicular'axis of the stack and with their peripheral surfacesshaped and arranged to bend the sheets against the peripheral surface ofthe said main roller and into the range of the counter-roller, androtary means for holding the bent sheet in contact with the main rollerbefore engagement of the sheet by the counter-roller.

5. Apparatus whereby the lowermost sheet is withdrawn in a diagonaldirection from a stack of single or folded sheets-or the like,comprising. means for forming a recess between the lowermost sheet andthe one next thereto, tongues adapted to penetrate said re cess to benddown the lowermost sheet, a main roller mounted beneath the stack, arecessed counter-roller co-operating therewith, a pair of rotary memberswith excisions therein to form said tongues and shaped with peripheralsurfaces concentric to the peripheral surface of the main roller, andatleast one rotary arm for engaging the bent sheet and temporarily holdingsame against the main roller.

6. Apparatus whereby the lowermost sheet is withdrawn in a die onaldirectionfrom a stack of single or 01 ed sheets or the like, comprisingmeans for forming a recess between the lowermost sheet and the one nextthereto, tongues adapted to penetrate said recess; to bend down thelowermost sheet, a main roller mounted beneath the stack, a recessedcounter-roller u co-operatin'g therewith, a pair of'rotarylgell-shapedmembers with excisions therein to term said tongues and havingperipheral surfaces concentricto the mainroller to bendthe sheet towardssaid main roller and into the range of the counter-roller, at least onerotary arm mounted on an axis parallel to the axes of the bellshapedmembers and an arc-shaped portion arranged eccentrically to said axisand carried by said am for engaging the sheet and pressing sameintoclose contact with the main roller preparatory to engagement ofthe sheetby'the counter-roller.

In testimony whereof we have signed our names to this specification.

r ALF

